48 DUDLEY MEMORIAL VOLUME 



described as having upon the ventral surface leaf -like scales or amphigastria, 

 but Schiffner found that these were not present in Calycularia radiculosa, 

 and the writer's investigations coniirm this. These leaf-like scales are re- 

 placed by multi-cellular hairs (Fig. 4, Bh), such as are common on many 

 other' thallose Jungermanniales. The terminal cell is enlarged and probably 

 secretes mucilage for the protection of the thallus apex. 



The latter is turned strongly upward (Figs. 5, Bj 8, A) and it is 

 almost impossible to make satisfactory sections parallel with the surface 

 of the thallus. Figures 4, D and 5, B show sections whdch are approximately 

 parallel; but as these are somewhat oblique, the apical cell appears some- 

 what shorter than it really is. In this view it appears somewhat oblong in 

 outline, and it is evident that segments are cut off both from the lateral and 

 from the basal portions. In vertical horizontal sections the apical cell shows 

 certain variations, resembling in this respect the genus Pellia. While Pellia 

 epiphylla has an apical cell with a single basal segment extending the whole 

 length of the thallus, in P- calycina a vertical section shows two sets of seg- 

 ments, dorsal and ventral, such as occur in certain species of Pallavicinia, as 

 ■ well as in the Marchantiales and in Anthocros. In Calycularia radiculosa 

 both of these tjrpes were found. The type found in Pellia epiphylla (See 

 Fig. 4, B, C) were common in the smaller plants, but it was not at all clear 

 whether there really is any definite relation between the thickness of the 

 thallus and the form of the apical cell. The second type is shown in 

 Figure 4, A. 



Where branching takes place it seems to be a true dichotomy, but whether 

 one of the branches retains the original apical cell or whether two new apical 

 cells are developed, was not investigated. 



THE MALE PLANT. 



The male plants (Fig. 1) are usually quite short, often being scarcely 

 longer than broad, and as we have already stated, antheridia are sometimes 

 found upon plants which are not more than 5 mm. in length. The antheridia 

 are in small groups, seldom more than ten together, and are much less nu- 

 merous than is the case in either Morkia or Blyttia. In the restriction of 

 the antheridia to such a limited region the plants suggest Makinoa, but the 

 whole antheridial group is not subtended by a common envelope as in Makinoa, 

 though the antheridia occupy a more or less well-marked depression or cavity 

 upon the dorsal surface of the midrib. Each antheridium is subtended by a 

 much laciniated scale. The scales are often more or less confluent, so that 

 imperfect chambers are formed (Fig. 5, C) about each antheridiiui).' As a 

 rule, only one receptacle occurs upon the plant, but in a few of the larger 



